A MIME Body Part for ODA
Carries office documents in email using a standard format
Alvestrand, H., "A MIME Body Part for ODA", RFC 2161, DOI 10.17487/RFC2161, January 1998, <https://www.rfc-editor.org/info/rfc2161>.
@misc{rfc2161,
series = {Request for Comments},
number = 2161,
howpublished = {RFC 2161},
publisher = {RFC Editor},
doi = {10.17487/RFC2161},
url = {https://www.rfc-editor.org/info/rfc2161},
author = {H. Alvestrand},
title = {{A MIME Body Part for ODA}},
pagetotal = 5,
year = 1998,
month = jan,
} RFC text
Contents
Network Working Group H. Alvestrand
Request for Comments: 2161 UNINETT
Category: Experimental January 1998
A MIME Body Part for ODA
Status of this Memo
This memo defines an Experimental Protocol for the Internet
community. It does not specify an Internet standard of any kind.
Discussion and suggestions for improvement are requested.
Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (1998). All Rights Reserved.
Table of Contents
Status of this Memo ........................................ 1
1 Introduction .............................................. 1
1.1 The Application/ODA MIME content-type ................... 1
1.2 ODA - application/oda ................................... 2
2 Security Considerations ................................... 3
3 References ................................................ 4
4 Author's Address .......................................... 4
5 Full Copyright Statement .................................. 5
1. Introduction
This document contains the definitions, originally contained in RFC
1495 and RFC 1341, on how to carry ODA in MIME, and how to translate
it to its X.400 representation.
1.1. The Application/ODA MIME content-type
The "ODA" subtype of application is used to indicate that a body
contains information encoded according to the Office Document
Architecture [ODA] standards, using the ODIF representation
format. For application/oda, the Content-Type line should also
specify an attribute/value pair that indicates the document
application profile (DAP), using the key word "profile", and the
document class, using the keyword "class".
For the keyword "class", the values "formatted", "processable" and
"formatted-processable" are legal values.
Thus an appropriate header field might look like this:
Content-Type: application/oda; profile=Q112; class=formatted
Consult the ODA standard [T.411] for further information.
The Base64 content-transfer-encoding is appropriate for carrying ODA.
1.2. ODA - application/oda
X.400 Body Part: ODA
MIME Content-Type: application/oda
Conversion: None
Comments:
The ODA body part is defined in the CCITT document T.411 [T.411],
appendix E, section E.2, "ODA identification in the P2 protocol of
MHS"
An abbreviated version of its ASN.1 definition is:
oda-body-part EXTENDED-BODY-PART-TYPE
PARAMETERS OdaBodyPartParameters
DATA OdaData
::= id-et-oda
OdaBodyPartParameters ::= SET {
document-application-profile [0] OBJECT IDENTIFIER
document-architecture-class [1] INTEGER {
formatted (0)
processable (1)
formatted-processable(2)}}
id-et-oda OBJECT IDENTIFIER ::= { 2 8 1 0 1 }
Mapping from X.400 to MIME, the following is done:
The Parameters.document-application-profile is mapped onto the MIME
parameter "profile" according to the table below.
Profile OBJECT IDENTIFIER
Q112 { iso (1) identified-organization (3) ewos (16)
eg (2) oda (6) profile (0) q112 (1) }
The Parameters.document-architecture-class is mapped onto the MIME
parameter "class" according to the table below.
String Integer
formatted formatted(0)
processable processable(1)
formatted-processable formatted-processable(2)
NOTE: This parameter is not defined in RFC 1341.
The body of the MIME content-type is the Data part of the ODA body
part.
When mapping from MIME to X.400, the following steps are done:
The Parameters.document-application-profile and Parameters.document-
architecture-class are set from the tables above. If any of the
parameters are missing, the values for Q112 and formatted-processable
are used.
It is an option for the gateway implementor to try to access them
from inside the document, where they are defined as
document-profile.document-characteristics.document-architecture-class
document-profile.document-characteristics.document-application-
profile
Gateways are NOT required to do this, since the document-
characteristics are optional parameters. If a gateway does not, it
simply uses the defaulting rules defined above.
The OBJECT IDENTIFIERs for the document application profile and for
ODA {2 8 0 0} must be added to the Encoded Information Types
parameter of the message envelope.
2. Security Considerations
ODA body parts have the natural propensity of complex structures that
it is hard to find out what the parts are capable of.
Moreover, ODA is an extensible architecture, where new content
portions may be added at any time, so that the threats posed by this
body part may change over time.
However, no security risks related to ODA are known at this time.
3. References
[MIME]
Freed, N., and N. Borenstein, "Multipurpose
Internet Mail Extensions (MIME) Part One: Format of Internet Message
Bodies", RFC 2045, November 1996.
[T.411]
CCITT Recommendation T.411 (1988), Open Document Architecture
(ODA) and Interchange Format, Introduction and General
Principles.
4. Author's Address
Harald Tveit Alvestrand
UNINETT
Postboks 6883 Elgeseter
N-7002 TRONDHEIM
Phone: +47 73 59 70 94
EMail: Harald.T.Alvestrand@uninett.no
5. Full Copyright Statement
Copyright (C) The Internet Society (1998). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
AI ELI5
On this page
§1Office Documents in Email
The Office Document Architecture (ODA) is an international standard for formatting documents. X.400 is an older email system that understands ODA documents natively. Internet email uses MIME for attachments. When email travels between X.400 and Internet systems, documents need translation. This document specifies how to represent ODA documents in MIME so that mail gateways can reliably carry them between systems.
Two old email systems need to understand office documents. One knows ODA, the other knows MIME. This explains how to translate between them.
§2The MIME Content-Type
ODA documents are sent as MIME type application/oda. Two required parameters describe the document: profile (such as Q112 for a common profile) and class (one of formatted, processable, or formatted-processable). For example: Content-Type: application/oda; profile=Q112; class=formatted. The document body is encoded using Base64 content-transfer-encoding. When no parameters are provided, defaults of Q112 profile and formatted-processable class are used.
The email says "this is an ODA document" and tells what kind it is. The document data is then encoded as text for email.
§3Translation Between Systems
Mail gateways map the MIME parameters to X.400 body part parameters and back. The gateway may optionally try to read profile and class information from inside the document itself, though this is not required. When translating from X.400 to MIME, the gateway extracts the document application profile and architecture class from the X.400 ODA body part. When translating from MIME to X.400, the gateway reads the parameters from the Content-Type header and sets the X.400 ODA body part parameters accordingly.
When documents cross between the two email systems, gateways read the labels, change them to the other system's format, and send the document on its way.